CN105024355A - Method for mutual interlocking of transformer inlet wire power supply and security power supply - Google Patents

Abstract

The method of mutual interlocking between the transformer incoming power supply and the security power supply belongs to the field of power system operation, (1) Connect the secondary circuit breaker of the 1# main transformer to the security power supply cabinet and the secondary circuit breaker of the 2# main transformer to the security power supply Circuit breaker cabinet; (2) From the relay protection room of the secondary circuit breaker of the 1# main transformer, the normally closed contact signals of a pair of circuit breakers are connected in series to the closing circuit of the security power supply; (3) From the 2# main transformer The relay protection room of the secondary circuit breaker leads a pair of normally closed contact signals of the circuit breaker into the closing circuit of the security power supply in series; The normally closed contacts of the circuit breaker are respectively connected in series to the closing circuits of the 1# main transformer and the 2# main transformer. The invention effectively prevents the accident of burning high-voltage electrical equipment caused by the closing of two power sources, and ensures the safe and stable operation of the electrical equipment.

Description

Interlocking method between transformer incoming power supply and security power supply

technical field

The invention belongs to the field of power system operation, and is mainly used in power systems such as step-down stations, high and low voltage substations, power distribution stations and the like.

Background technique

The 110KV substation has two power supplies with two main transformers, and each transformer runs with a section of 10KV bus. There is a security power supply in each section of 10KV. When the whole station loses power, other 10KV loads will be carried by the security power supply to reduce losses. Due to the phase difference between the security power supply and the secondary switching power supply of the main transformer, during operation, there is no mechanical and electrical interlock between the security power supply cabinet and the secondary switch of the main transformer, and the high-voltage electrical equipment may be burned due to the two power supply loops. ACCIDENT.

Contents of the invention

In order to prevent the above accidents, the present invention provides a method for interlocking the incoming power supply and the security power supply.

The technical scheme of the present invention is: including the secondary control loop of the main transformer and the secondary control loop of the security power supply.

The secondary circuit of the 110kV main transformer includes: the operation box and control circuit of the primary and secondary circuit breakers of the main transformer; the circuit of the double-bus voltage switching device; the circuit of the measurement and control device of the transformer; Protection circuit; transformer on-load voltage regulation and tap position circuit.

(1) Lay a 4-core cable respectively, connecting the secondary circuit breaker of 1# main transformer to the security power cabinet and the secondary circuit breaker of 2# main transformer to the security power circuit breaker cabinet;

(2) From the relay protection room of the secondary circuit breaker of the 1# main transformer, the normally closed contact signals of a pair of circuit breakers are connected in series to the closing circuit of the security power supply;

(3) From the relay protection room of the secondary circuit breaker of the 2# main transformer, the normally closed contact signals of a pair of circuit breakers are connected in series to the closing circuit of the security power supply;

(4) From the secondary terminal block of the circuit breaker relay protection room of the security power supply, a pair of normally closed contacts of the circuit breaker are connected in series to the closing circuits of the 1# main transformer and the 2# main transformer respectively.

The invention effectively prevents the accident of burning high-voltage electrical equipment caused by the closing of two power sources, and ensures the safe and stable operation of the electrical equipment.

During normal operation, the security power circuit breaker is open, its normally closed point is closed, the closing circuit of the main transformer is intact, and it is ready for operation. When the safety power circuit breaker is closed and running, the normally closed point of the safety power supply is opened in the closing circuit of the main transformer, which causes the closing circuit to be blocked and cannot be closed.

When the main transformer is closed and running, its normally closed point is opened, and the closing circuit of the security power circuit breaker is disconnected, so it cannot be closed. Only when the circuit breaker of the main transformer is opened, its normally closed point can be closed, and the circuit breaker of the security power supply can meet the conditions of closing and transmitting power, which can prevent the closed-loop operation of different phase power supplies and effectively ensure the safe operation of the power grid.

When the security power supply is closed and running, the secondary circuit breaker of the main transformer cannot be closed because the normally closed point of the security power supply is open and the closing circuit is blocked. Similarly, when the main transformer is closed and running, the security power circuit breaker cannot be closed. , thus eliminating the closed-loop operation of different-phase power supplies, effectively ensuring the safe operation of the power grid.

Detailed ways

(1) Lay a 4-core cable respectively, connecting the secondary circuit breaker of 1# main transformer to the security power cabinet and the secondary circuit breaker of 2# main transformer to the security power circuit breaker cabinet;

(2) From the relay protection room of the secondary circuit breaker of the 1# main transformer, the normally closed contact signals of a pair of circuit breakers are connected in series to the closing circuit of the security power supply;

(3) From the relay protection room of the secondary circuit breaker of the 2# main transformer, the normally closed contact signals of a pair of circuit breakers are connected in series to the closing circuit of the security power supply;

(4) From the secondary terminal block of the circuit breaker relay protection room of the security power supply, a pair of normally closed contacts of the circuit breaker are connected in series to the closing circuits of the 1# main transformer and the 2# main transformer respectively.

Claims (1)

1. a method of reciprocal interlocking between transformer incoming power and emergency power supply,

(1) lay 4 core cables respectively, be attached to emergency power supply cabinet from 1# main transformer secondary circuit breaker and 2# main transformer secondary circuit breaker is attached to emergency power supply breaker cabinet;

(2) the normally closed contact train of signal of drawing a pair circuit breaker from the relay protection chamber of 1# main transformer secondary circuit breaker connects the closing circuit of emergency power supply;

(3) the normally closed contact train of signal of drawing a pair circuit breaker from the relay protection chamber of 2# main transformer secondary circuit breaker connects the closing circuit of emergency power supply;

(4) connect respectively in the closing circuit of access 1# main transformer, 2# main transformer from the normally closed contact of extraction a pair circuit breaker the circuit breaker relay protection chamber secondary terminals row of emergency power supply.